Very nice product. It is very standards compliant, it have pluggable languages for stored procedures e.g: perl, tcl, or its own pgplsql).
pgplsql is very similar to to Oracle PL/SQL so if you are familliar with that you will quickly get up to speed as a developer.

It comes as a command line application, but there are several graphical admin frontends available as separate downloads, among them the postgresql specific pgAdmin III. If you decide to use it from the command line the cli client is very functional, with built in help system and autocomplete features.

At the moment it probably have the fastest full text search engine there is all categories (open source or otherwise). The fulltext search also have support for a long list of languages.